Flexible joint for underground electrical conduits



'oint for connecting -v AUNITED STATES PATENT OFFICE.

' snfrga E. Husten-fr, or CHICAGO, 'ILLINois FLEXIBLE JOINT FOR' U'NDERGB ouNb ELECTRICAL-concurre.

'SPECIFICATION forming p'art of Letters Patent Nd. 352,754, dated November 16,1886. y

Application tiled June 14,1886.

Tvall Awhom', it may concern:

Beit known that I, SETE E. HURLBUT, re siding atrChicago, in the county of Cook and State of Illinois, and a citizen of the United States, have invented a new and useful AImprovement in Flexible Joints for Underground Electric Conduits, of which the following is a full description, reference being had to the accompanying drawings, in which- Figure 1 is a sectional elevation showing the joint applied to an electrical conduit; Fig. 2, a crosssec-tion on line w :v of Fig. 1; Fig. 3, a cross-section on line y y of Fig. 1; Fig. 4, adetail in section showing the coupling-ring.

t My, invention relates to underground conduits for electric conductors, and is particularly designed as an improvement upon the invention forming the subject-matter of United States Patent No. 340,046, granted to Daniel N. HurlbutfApril 13,1886. In saidpatentis shown a water-tight and gas-proof iiexible the sections of which the underground conduit is composed. I retain the principal or main features of such patented invention and providev the improvements hereinafter specified and claimed, which will insure a more perfect and simple flexible joint,

and render the operation of forming the jointmore easy and expeditious than in the patent referred to.

In thevdrawings, ring having an interior larger than the l diameter A represents a collar or of the pipe ends which it is to encircle. This collar or ring Av can be made of cement', iron, or other suitable material, and is provided with openings a for the ppuring in of the liquid filling or cement, and its interior .face is provided with semicircular grooves b, two on each side of the center of the ring, and between the semicircnlar rooves b on each side 1s a wider groove, c, in

the form of construction shown.

a B representsropes of asbestus or pressi ble material that will yield somewhat and still be firm enough to maintain a unity when the ringv A, with the retaining material B, encircles the pipe end. The asbestus ropes or retainers B tit within the interior of the ring A, running entirely around in the grooves b, and they project beyond the inner face of the ring or collar A, to produce ahole of a less diameter than the diameter of the pipe end. These diameter somewhat other comf and i't will be seen Serial No. 205.123. (No model.)

,asbestus or other flexible ropes are introduced into the grooves b in the collar or ring A, and are held -therein by their ownelasticity; or, 'in other words,'.they are inserted. inthe grooves :and are held by their springiness, which causes them to form an arch, so that they cannot drop out of place. a t j Gis aliquid filling of asphaltum or other material that will harden somewhat after being poured in, which fillingis locatedin the groove c on ea h sidegof the center of the ring and around the pipe end between the retainers B, and is poured into place through the openin g a'. D represents the sections of pipe, the form represented being a conduit 'or pipe designed for electrical conductors; but the device is to be used in connection with sewer, drain, or other pipe where it is desirable to have a close tight joint at the juncture ofthe sections. As shown, the end of each pipe D is tapered, as at d, to -facilitatethe slipping of the pipe end into the ring or collar. 't

In use the ring Ahas inserted in the grooves b on its inner face the retainers or packing B, and is then ready to be applied to the pipeV ends by inserting such ends into the ring, and the act of inserting compresses the packing or retainers B, adjoining the surface of the pipe, so as to produce a slightly-flattened surface,

B and make a close fit between the ring A,

packing B, and pipe end. The liquid'asphaltum or cement is poured into the hole a, filling the space` in the groove c and between the packing or retainers B, as shown in Fig. 1, and

as the packing or retainers vare in close contact with. the surface of the ring and the surface of the pipe, the liquid material can only extend to and ll the space between the two packings or retainers.

tight, as the packing or retainer B in and of itself makesa fairly tight joint, which, with the liquid material, ismadel absolutelytight, that the pipe ends do not abut one against the other, and' that between the extreme end of each pipe end and the interior face of the ring or collar A is a space, which is vacant or left unfilled with either the and also that at each end of the collar or ring and between the interior face of the collar or which serves to expand the packing or retainer i The joint thus produced is very close and Ico liquid material or the packing or retainer B,

ring and the exterior surface of ,the pipe is an unfilled space, so thatvwith the ends not abutting the pipe-section is free to move to some extent, allowing the pipe-section to j drop, yor be otherwise changed without affecting the tightness of the joint. I y

In the Patent No. 340,046, above Areferred to, is disclosed a exible joint ,for pipe-sections, which is flexible, so as to allow for theupheaving or settling of the pipes. Said joint is formedby wrapping a flexible packing around the pipe-section to be entered into an adjoining section and then pouring a liquid filling, which, when 'c ool, remains permanently plastic in 'a spaceformed between the flexible packingon the entering pipe-section. packingin the patent referred to is held in place by tying or other means, and is very liable to drop out of plac or become disarranged when the joint is being formed. In the present invention, however, the 'ex'ible packing or so-called retainers are sprung into place and are held in arihg or collar, which is entered by the pipe-sections to be joined. This construction and manner of forming the -simplicity and removes '1."he1'iexible manently-plastic filling C,

Lcommunicating with joint, as heretofore described, insures greater the objectionspossessed by the joint shown in the patent above referred to. In the present invention I also dispense with the shoulders on the pipe-sec- 3c tions heretofore required to form seats for the exible packing, and other advantages are obtained which will readily be apparent.

What I 'claim as new, and desire to secure by Letters Patent, is 3 5 The combination, with two conduit-sections capable of movement relative to each other, of -a ring or collar having interior circumferential grooves, b, the flexible packing B, held in said grooves by its own elasticity and projecting beyond. said grooves, the grooves c, arranged between said packing B, and the percontained in said or collar having holes a the grooves c, substan- 45 grooves c, the ring 'tially as described.

SETH E. HURLBUT. Witnesses:

ALBERT H. ADAMS, 0. W. BOND. 

